Physical change .. you cannot undo chemical ... physical is like bending , shattering a mirror , denting something ..
chemical would be rust or something .
____NaNO3 + ___PbO --> ___Pb(NO3)2 + ___Na[2]O
To balace the eqaution, you need to have the same number of atoms for each element on both the reactant (left) and product (right) side.
To start off, you wanna know the number of atoms in each element on both sides, so take it apart:
[reactants] [product]
Na- 1 Na- 2
N- 1 N- 2(it's 2 because the the subscript [2] is outside of the parenthesis)
O- 4 O- 7 (same reason as above)
Pb- 1 Pb- 1
Na is not balanced out, so add a coefficient to make it the same on both sides.In this case, multiply by 2:
2NaNO3
Now Na is balanced, but the N and O are also effected by this, so they also have to be multiplied by 2 and they become:
Na- 2 Na- 2
N- 2 N- 2 (it balanced out)
O- 7 (coefficient times subscript, plus lone O) O- 7 (balanced out)
Pb was already balanced so no need to mess with it, just put a 1 where needed (it doesn't change anything).
Now to put it back together, it will look like this:
2NaNO3 + 1PbO --> 1Pb(NO3)2 + 1Na[2]O
Answer:
= 0.030 M
Explanation:
We can take x to be the concentration in mol/L of Ag2SO4 that dissolves
Therefore; concentration of Ag+ is 2x mol/L and that of SO4^2- x mol/L.
Ksp = 1.4 x 10^-5
Ksp = [Ag+]^2 [SO42-]
= (2x)^2(x)
= 4x^3
Thus;
4x^3 = 1.4 x 10^-5
= 0.015 M
molar solubility = 0.015 M
But;
[Ag+]= 2x
Hence; silver ion concentration is
= 2 x 0.015 M
= 0.030 M
Answer:
actually answer should be helium
